iMOXS-SEM

The brochure of the iMOXS-SEM with detailed technical data is available as pdf for download (270 kB). 

For the first time an XRF-module with a capillary optics enables performing x-ray micro fluorescence analysis at SEM!

In SEM a focused electron beam scans the surface of a sample and generates its image. The also excited x-ray fluorescence can be used to identify the sample composition. The advantage of this electron probe microanalysis (EPMA) is the high spatial resolution. However, detection limit ranges between 1 and 0.1 weight-% due to electron-induced bremsstrahlung background. A photon excitation option in SEM would reduce significantly the background and also the detection limits to the level of x-ray fluorescence analysis (XRF). High intensity of the exciting radiation within a small spot on a sample is achieved by using focusing x-ray capillary optics.

The µ-XRF-module – iMOXS-SEM - consists of a low-power x-ray tube, a focusing polycapillary optic, an adjustment unit, a HV-supply and control unit CSU and the software package iMOXS-Quant for spectrum evaluation and quantification. The design of the module enables its easy adaptability for SEMs of different manufacturers (FEI, Hitachi, JEOL, TeScan, Zeiss, etc.). iMOXS-Quant offers standardless quantitative analysis, analysis with single standards and processing light elements results of EPMA.

X-ray capillary optics is the decisive element of this instrument, because it enables local fluorescence excitation with a high intensity at a large distance from the source.

The first figure shows the iMOXS-SEM. The second figure presents the x-ray spectra of a LiAlCaF₆:Cr laser crystal with electron and photon excitation that demonstrates the differences in excitation efficiency and spectral background.